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What is >> Variable bit rate?

Old 06-27-02, 05:33 PM
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What is >> Variable bit rate?

I was looking to bring the bit rate down to 128 instead of 192 when uploading cds. I can't seem to tell the difference when listening to the mp3s in my car.

Anyhow, I have heard that it's better to use variable bit rates? I always thought this meant varying the bit rates you use: 128, 160, 192, maybe some 320's. I never had a problem using the 128's I DL from others and the 192's I upload and use.

But, I see on EAC when I hit "F11" I have the option to upload at variable bit rates of: 128 and 192. There are others but the only 2 I am interested are the 2 I mentioned.

Can someone explain this variable bit rate thing to me?
Thanks for any help you can offer!

Last edited by LX98Civic; 06-27-02 at 05:35 PM.
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Old 06-27-02, 05:36 PM
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Basically, it's supposed to use an intelligent 'algorithm' to judge where in each musical file more data, or bits, are needed. It supposedly can increase the sonic quality WITHIN ONE FILE OR TRACK without hugely expanding the filesize in MBs.

Personally, I don't hear much difference, but then again my computer speakers suck.
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Old 06-29-02, 08:12 PM
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I can tell the difference on my home theater system. Hands down 196 blows away 128 anyday. But I also have a high end system w/ high end cables. Now on my computer I can't tell the difference.
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Old 06-30-02, 09:29 AM
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Originally posted by TheKobra
I can tell the difference on my home theater system. Hands down 196 blows away 128 anyday. But I also have a high end system w/ high end cables. Now on my computer I can't tell the difference.
I tried the variable rate and it takes LAME wayyyyyyy to long to extract the WAV files this way. I just went with a constant 128 instead of 192 or a variable. 128 sounds fine in my car
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Old 06-30-02, 11:02 AM
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VBR is your best feaking friend when it comes to MP3 ripping.

Quick description:

MP3 compression massively reduces file sizes from WAV, but the audio loses some data, which is why it doesn't sound as good. As you compress more tightly, the resulting file gets smaller, but it sounds worse because you've lost more data. Now if you're compressing some "simple" sound, you won't notice the difference; but more "complex" sound will be noticeably duller and tinnier.

Normally, you set the bitrate constantly throughout the MP3, and your software compresses tyhe audio with equal "tightness" through the whole music track. You can choose a low bitrate (very tight compression), so the file is very small but doesn't sound great; or a high bitrate (not as tight), so the file is larger but sounds better.

VBR improves this by compressing at different rates. First, recognize that almost any music piece has both "complex" section and "simple" sections. Those parts of the music track that are "simple" get compressed more tightly; those parts that are more "complex" get compressed less. So, you get the best of both worlds: a smaller file size that still sounds good.

- David Stein
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Old 08-26-03, 12:23 AM
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I encoded several mp3s with VBR of 160 kbps (using EAC / LAME). When I play the mp3s with WMP, they all say ~400 kbps. Is that normal?
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Old 08-26-03, 07:40 AM
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Originally posted by namja
I encoded several mp3s with VBR of 160 kbps (using EAC / LAME). When I play the mp3s with WMP, they all say ~400 kbps. Is that normal?
A lot of the mp3 players and player software can't really figure out variable bit rates (VBR) that well, and will often report them incorrectly. I'm not sure why. Run it in Winamp and you should see the bit rate constantly changing up and down. Then you know you have a VBR recording.
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Old 08-26-03, 07:53 AM
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I think most of you are talking about ABR (average bit rate). It's basically the same thing, only you set a target bit rate you want to stay near.

In VBR, you set the max and min bit rates.

When making mp3s, I uses use 160ABR or just set VBR to go between 128 and 192.
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